Internal-combustion engine



Oct. 23, 1928. v- 1,688,550

N. E. METHLIN INTERNAL COMBUSTION ENGINE Filed Dec. 5, 1925 5Sheets-Sheet 1 Oct. 23, 1,928. 1,685,55Q

N. E. METHL|N INTERNAL COMBUSTION ENGINE Filed Dec. 1925 5 Sheets-Sheet2 Oct. 23, 1928. 1,688,550

N. E. METHLIN INTERNAL COMBUSTION ENGINE Filed Dec. 1925 5 Sheets-Sheet3 Oct. 23, 1928. 1,688,550

N. METHLIN INTERNAL COMBUSTION ENGINE Filed Dec. 5, 1925 5 Sheets-Sheet4 Oct. 23, 1928. 1,688,550

N. EQMETHLIN INTERNAL COMBUSTION ENGINE Filed Dec. 5, 1925 5Sheets-Sheet 5 v Patented Get. 23, 19 28. i

UNITED-STATES f;

NICOLAS EMILIEN METHLIN, 0F PARIS, FRANCE, ASSIGNOR T0 ,scnnnrnnn acorn,0F PARIS, FRANCE, A LIMITEDJ'OINT-SITOGK COMPANY onrnANoE.

- IntrnRnAn-coMBUsrIon ENGINE.

Application filed December3,1925, Serial No. 73,070, and inFrance-January 16,1925.

It is known that the object in scavenging the products of combustion inengines employing an explosive mixtureiis to scour the combustionchamber of the products which. are left in it, by introducing into thecylinder, towards the 'end'oi the 'exhauststroke,

a certain amount of air under pressure, profvided by an externalsource=of supply.

Thisair thus takes the. place of the burnt gases and forces them/beforeit into the ex-. ha'ust pipe, so, that at the beginningof the suctionstroke the combustion chamber contains nothing. but almost pure airwhich is carburetted by thegasdrawn in during theadmission stroke andenables a much higher output topbe obtained from the machine,

while improving the ignition of the charge. In known arrangements,scavenging" is generally assured, either by a means of valves controlledby cams and levers, orby means of an annular member mounted on the rodof the admission" valve. H

The first arrangement is complex, and

moreover, the control of the valves by cams and rollers does not permitof'obtaining openings and closings which are suitably rapid to assurethe largeopenings necessary: for the passage of the air introducedin arelativelyshort time. g In the second arrangement, the annular memberuncovers the scavenging orifices not only at the commencement ofthelifting of the admission valve to eii ect' scavenging, but likewiseat the'time of closing of thesame, which causes a choking efiect of theair introduced, so that, when the admission valve is on its seat, theair under pressure remains in communication with theinterior of theadmission chamber and may consequently penetrate into thecollectorofgas; and thus cause untimely explosions. Such; an arrangement,moreover, rendersit difiicult to assure a good explosive -mixture withweak charges. Finally, these two arrangements, donot permit ofadaptationto existing machines,

' .Figure whereof the valves, or at-least'the'exhaust valve,are'actua'ted by eccentrics.

1 It s characterized by the fact that the cally, the closing member maybe controlled with the aid of lever.

-In the example illustrated it has been a crank by the exhaust valveassumedthat the distributor is: provided with a valve connected on theone hand to the collector of scavenging air under pres"- sureand on theother hand, by a suitable pipe, to the corresponding admission'chamber..W'ith such an actuating arrangement the valve ofthe' distributor iscontrolled by the exhaust ivalve,'which is rational, since,

the scavenging'has to cease as soon as this valve rests on its seat.

Finally the connec tion between the valve lever and the v l rofithedistributorjis such; that the latter is given 'afrapld opening andclosing movement in. order'that it Will'havefa largesection-ofopenin'gduring the whole of its action.f. v. I 1 Figures 1 and 2illustrate, by way of example, and inside and front elevation.respectively, the "device'fitted to a working hereinbefore mentioned.

Figure 3. illustrates in section thead in der provided with the. knownvalve gear I mission chamber of the latter with thescavenging pipe.

Figure 4' illustrates an exhaust chamber,

connected to the scavenging device.

Figure 5 shows a longitudinal section through the valve (Figs 3, 4 and5' arev drawn to a larger scale than Figs. 1 and 2). Figure 6 is adiagram of the distribution phases of the engine.

is a diagram o'f the'motions of the mechanism of the scavengingair'distributing valve. i

I Figures 8, 9 and=10 show'the different positions of the scavenging airdistributing valve during the working of the engine.

. In Figures 1 and Q, 1 isthe working cylinder, 2 the admission chamber,3 the exhaust chamber, it the scavenging air valve, 5the collector ofscavenging air underpressure, 6 the pipe connecting the scavenging airdistributing value to the admission chamber, 7 the eccentric actuatingthe admissionand exhaust valves, 8 the eccentric actuating the airandgas distributing-valves, 9 the admission rod, 10 the exhaust rod, 11,11 the lever, pivoted at 11, actuating the exhaust valve.

The valve 12 of the distributor 4 (see'Fig. is connectedby means of acrank 17' and the small connecting rod 13 to the arm 11 of the lever 11,11'. a

Fig. 6 illustrates the stroke of the piston or rotation of the drivingcrank, the direction of. rotation being indicated by. an arrow. Thereference characters E and F represent the dead center positions of thepiston, and the reference characters A and B rep resent, respectively,the opening and closing of the exhaust valve relative to the stroke ofthe. piston. :Thus the period of rotation during which the exhaust valveis open is represented by the are A B. r

Fig. 7 represents diagrammatically the movementsofthe mechanismoperating the exhaust valve and the distributor 12 which is illustratedin Fig, 4. In'FigpTpoints e and 6 correspond to points e'and Ziof Fig. 4

and indicate the extreme positions of the arm 11 operating the exhaustvalve, and points 0' and b similarly indicate the ex treme positions ofthe distributor 12, 0 corresponding to the position-'0 of the arm 11.During the strokeA B the lever 11 travels over the arc 6-.-Zl0} (Fig. 7and the valve 12 moves over the arc a b a ,"so that this valve opens-andcloses the ports of the distributor l, and, consequently,thecommunication between the scavenging air collector 5 and the admissionchamber 2 at the momentwhen the exhaust valve lifts and closes. Figure 8shows the position of the valve 12 corresponding to these tWo points;Apart from the exhaust stroke, the collector- 5 is cut off fromcommunication with the admission chamber 2 and the scavenging air underpressure cannot'therefore enterinto the latter.

The referencecharacters C and D represent, respectively, the opening andclosing of the admission valve 14;, and the arc G-D therefore representsthe period of rotation of the driving crankduring which said valve isopen. Atjthe point C, with'a suitable angle of advance, the admissionvalve 14:

(Fig. 3) lifts, but the atmospheric air and gas distributing valves 15.continue tocover the ports of the admission chamber. At this moment thevalve 12 of the distributor'isin the position shown in Figure 9; theports 'of this valve are fully open and the scaveng .ing air, passingthrough the pipe 6, enters valve 15 is not quiteQfluid-tight.

while, the arc C ,B is traced. At the point B, the exhaust valve restson its seat. and the distributing valve 12 is in the position shown inFigure 8, covering thus the ports of the distributor, so that thescavenging air ceases to enter into the cylinder. The distributingvalves 15 of the admission chamber 2 then, uncover the ports of thelatter, and the atmospheric air and "the as are drawn into. the cylinderuntil the end D of the suction stroke, with qualitygoverning'or during astroke which is a funetionof the power -required from the inachina 'withquantity governing. In the latter case, the distributing valves, themovement of which is inde pendentof that of the admission valve, closetheirports when the charge o-f mixture ad-. mitted is sufficient, thevalveonly returning toits seat when thedrivi'ng crank is at the P0intD.1

' Thus scavengin takesplace while the driving crank traces the arc CB,during which are the admission and exhaust valves are raised. 7 In orderto allon this scavenging to be effected, it is necessary, on the onehand to raise the admission valve with: a

suiiicient advance during which the'driving crank travels over the arcCE before armission chamber, while the valve 14::lS'Ci1OSed,

during only a very smallmovement of the tosayduring' a sufiicientlysmall'time for! this air under pressure not'to' pass into'the gaspipe ifthe corresponding distributing Further, the addition of the device to anexisting machine necessitates no "other niodification than the piercingof a port 16 .for admitting the scavenging airinto the 'admis-. sionchamber 2; e J

driving-crank, represented by the exhaust travel mlnus the scavengngtravel', thati's Finally,"the device isgoverned, once and forall,when'theengine is started, and its operation remains'unlform while it 1swork ing whatever he the power required of the machine.-'

Asmentioned "above, the scavenging-air distributor may comprise a rotaryvalve or a piston valve, or any other member which is'capable ofperforming the same function. Further it is .notabsolutely necessary toplace this'distributor near the-exhaust chamber, as shown inthefiguresrif the arrangement of the machine requires it, the distributormay be placed in another position, for

i an

- chamber, a control valve for controlling the supply of scavenging airto said admission chamber, and means for opening and closing saidcontrol valve and exhaust valve substantially simultaneously, saidvalves being adapted to admit scavenging airto said combustion chamberwhen said admission valve opens.

2. In an internal combustion engine having a combustion chamber andadmission and exhaust valves therefor, a lever operating said exhaustvalve, and a control valve operatively connected to said lever for admitting air underpressure to the admission valve port, said controlvalve being adapted to open prior to said'admission valve andto remainopen andto close with said exhaust valve.

3. In an internal combustion engine having a combustion chamber andadmission and exhaust valves therefor, means for scavenging the productsof combustion of said engine including a collector of air underpressure, means for connecting the latter to the admission valve port, avalve controlling the supply of air to said chamber,

and common means for opening and closing said last-named valve with saidexhaust valve. g

4. In an internal combustion engine havmg a combustiom chamber andadmission and exhaust valves therefor, means for supplying scavengingair to the admission valve" port of said chamber, a control valve forcontrolling the supply of said air, and means" operatively connected tosaid exhaustvalve for opening and closing said control valve"specification.

with said exhaust valve,-whereby'; air under pressure is admitted tosaid valve port be-' fore said admission valvelifts and is out ofi'therefromwhen said exhaust valve closes.

5. In combination with an internal combustion engine having a combustionchamher and admission and exhaust valves therefor, means for scavengingthe products of combustion from said chamber including a distributor ofair under pressure connected.

-with the admission valve port, a control valve for controlling thesupply of said air to said admission port, and means'opera- .tivelyconnecting said control valve and exhaust valve for operating saidvalves at the same time, whereby scavenging commences when saidadmission valve lifts and ends when said exhaust valve closes.

6. Inaninternal combustion engine of the type having a combustionchamber, ad-

mission and exhaust valves therefor, an admission chamber communicatingwith said combustion chamber through the admission valve port, andadditional valvescontrolling the admission ofair and gas to saidadmission chamber, scavengin means comprising a'collector of air un erpressure, a conduit connecting the latter with said admission chamber, arotary distributing valve for said conduit, and means for simultaneouslyopening and closing said exhaustvalve and said distributing valve.

7-. In an internalcombustion engine of the type having a combustionchamber, admission and exhaust valves therefor, an admission chambercommunicating with said combustion chamber through the admission valveport, and a pair of valves controlling the admission of air and gas to'said admission chamber, scavenging means comprising a collector of airunder pressure, a conduit connecting the latter with said admissionchamber, .a rotary distributing'valve in said conduit, and common meansfor simultaneously opening and closingsaid exhaust valve and saiddistributing valve, whereby air under pressure is admitted to saidadmission In testimony whereof I have signed this NICOLAS EMILIENMETHLIN.

chamber before said admission valve lifts and is cut off from saidadmission chamber when said exhaust valve closes.

